Conventionally, auto-cruising techniques to reduce the driver's fatigue, improve the riding comfort, and improve the fuel economy by maintaining the speed of a vehicle such as an automobile at a setting speed are known.
For example, PTL 1 discloses a hybrid electric vehicle control device that performs the above-mentioned speed control. This control device performs the control such that, in the case where a vehicle travels on an upslope, coasting is started from a point before the crest such that the speed at the crest point has an acceptable lower limit value to reduce the fuel consumption amount. In addition, PTL 1 includes a disclosure in which an energy loss such as a roll resistance is taken into consideration when a control device calculates the above-mentioned point.